1. Field of the Invention
The present invention relates to a packaging body for an object to be packaged, for example, a cassette case or the like, and more particularly, to a packaging body in which an opening tap is formed in a part of an adhered portion of an outer packaging film and a weakly adhered part with a slit is provided in the vicinity of the opening tap which gives a chance for unsealing the outer packaging film, to thereby improve unsealing of the outer packaging film.
2. Description of the Related Art
Conventionally, for example, when a tape cassette for an audio use, a tape cassette for a video use or the like is planned to be a commercial good and actually placed on the market, a cassette case accommodating therein the cassette of this kind is wrapped with an outer packaging film (ornamental film) and then put on sale.
As an outer packaging film of this kind, there has been used film material made of polypropylene (PP) or the like, which is excellent in toughness and has heat adhesiveness, and a cassette case to be packaged is wrapped with the film. The outer packaging film used for wrapping is sealed by heat-bonding an overlapped portion thereof.
As a general method for unsealing an outer packaging film with which a cassette case is wrapped, there is proposed such a method in which a cut tape is inserted into the outer packing film in advance, and upon unsealing, a leading tip end of the cut tape is pulled out in a predetermined guiding direction, while the tip end is picked up by fore-ends of fingers, so that the outer packaging film is torn and as a result the package comes to be unsealed. However, in the case where the cut tape is used, the leading tip end of the cut tape is difficult to be pinched by the fore-ends of fingers because the leading tip end is adhered to the surface of the outer packaging film. Or in the case where an outer packaging film is torn by the cut tape in circular fashion, the outer packaging film is left on the side of the cassette case, so that such the film left on the case is also manually burdensome in peeling off.
On the other hand, as a method for unsealing with no use of a cut tape, a packaging method is proposed in disclosure of, for example, Japanese Patent Application Publication No. Hei 8-72930. The method will be described with reference to FIG. 1.
An outer packaging film 2 wrapping a cassette case 1, which is an object to be packaged is sealed on a front face 3 of the body thereof and on both left and right side faces 4 and 5 thereof. Both end portions of the outer packaging film 2 are overlapped with each other on the front face 3 of the body of the object and then the overlapped is heat sealed to form a adhered portion 6. A non-adhered portion of the outer packaging film 2 is formed in a middle part of the adhered portion 6 and the non-adhered portion works as an opening tap 7 when the outer packaging film 2 is unsealed. Overlapped portions of the outer packaging film 2 are formed on left and right side faces 4, 5, as viewed, in the case where the outer packaging film is wrapped by a wrapping manner for a caramel, for example, and they are also heat sealed to form side adhered portions 8.
While the packaging body formed as mentioned above is unsealed in such a manner that an end of a finger or the like is inserted into the opening tap 7, an edge portion of the outer packaging film is picked up and the outer packaging film 2 is torn to be unsealed, the outer packaging film 2 having a high toughness made of polypropylene or the like has a problem that it is apt to be stretched with neither breakage nor tearing. If such an outer packaging film is unreasonably tried to be torn, the cassette case receives a strong force, which can cause a breakage of the cassette case. Moreover, while there is another proposal in which a slit 9 is provided in a part of the opening tap 7 and the slit gives an effective chance for easy tearing of the outer packaging film 2, even if a slit is simply provided, the outer packaging film is often wrongly torn, which tends to prevent the opening tap with a slit from being effective in unsealing the outer packaging film.